Last run at Washington Park? It has a 2.6 mile gravel loop and a 2.5 mile paved loop. And its design was inspired by Central Park of NYC.
Warm up 20+ minutes then 1 mile tempo, 5X 1 min on 1 min float, and finish with another mile tempo (latter mile got to be closer to 10K pace, so too fast). Cool down. Total 8 miles.